1. Field of the Invention
The field of the invention relates to printing apparatus, and more particularly pertains to a new and improved forced flow press dampening apparatus wherein the same directs pressurized flow through a predetermined gradient onto cooperative water from rollers and to direct the fluid flow onto a plate cylinder of a printing operation.
2. Description of the Prior Art
In printing, and more particularly in lithographic printing, a press plate cylinder has a non-printing area coated with a film of fluid from a dampening system that typically comprises water with further portions of the plate cylinder treated with ink from an ink-form roller, wherein the dampening system is arranged to provide a predetermined quantity of water to provide a balanced distribution on the plate cylinder. This is desirable to avoid imparting of excess water onto portions of the cylinder not utilized in a printing procedure. To solve the water/ink relationship upon the plate cylinder, the prior art has utilized various arrangements to impart appropriate amounts of water to the aforenoted plate cylinder. Examples of the prior art include U.S. Pat. No. 4,538,514 to Simeth wherein a dampening unit for a rotary printing operation includes a metering roller that directs fluid flow from a central conduit through the roller under pressure onto cooperating form rollers.
U.S. Pat. No. 3,911,815 to Banfer sets forth a dampening mechanism for feeding a film of water utilizing a conventional pick-up roll to direct the water to cooperating rollers and direct the water therefrom ultimately to a cooperating plate cylinder.
U.S. Pat. No. 3,923,936 to Davis, et al., illustrates a roller surface configuration wherein water is directed from the roller through capillary action in an effort to properly meter the water flow therethrough.
U.S. Pat. No. 4,016,811 to Zavodny sets forth a transfer roller for use in dampening mechanisms of printing presses utilizing spiral grooves to direct desired quantities of water to a plate cylinder.
U.S. Pat. No. 4,143,596 to Ivett sets forth a dampening system utilizing a brush roller to properly transfer a predetermined quantity of fluid to a cooperating plate cylinder.
As such, it may be appreciated that there is a continuing need for a new and improved forced flow press dampening apparatus wherein the same addresses both the problems of appropriately directing desired quantities of water in a desired ratio to a press cylinder and further effectively provide valving to effect this goal.